Multiple choice Which organ’s primary role is excretion, particularly water soluble wastes? Kidneys Liver Adrenal glands Pancreas Reveal answer Fill a bubble to check yourself A Correct answer Explanation The primary role of the kidneys is excretion, specifically filtering the blood to remove metabolic wastes, excess ions, and water-soluble toxins in the form of urine. While the liver processes toxins, it does not directly excrete urine.